Food storage and display device



Nov. 9, 1943. s-nLEs FOOD STORAGE AND DISPLAY DEVICE 2 sheet s-sneet 1 Filed Dec. 1, 1941 lllllllllllL .lullll ||IIIIL EQQUQHZMSZLZQS, BY M I Nov. 9, 1943. 5 s'nL s FOOD STORAGE AND DISPLAY DEVICE 2 Sheets-Sheet 2 Filed Dec.

INVENTOR.

Q ard/MGM Patented Nov. 9, 1943 UNITE D' STATES PATENT OFFICE roon- STORAGE AND DISPLAY mavron Edward M. Stiles, Burlington, Iowa Application December 1, 19*41, Serial'No. 421,165

(01. e2- .s.9.e

6. Claims.

' My invention relates to apparatus for the storage, preservation and display of food stuffs. More specifically, it relates to a cabinet having a plurality of storage compartments, isolated from each other and from the refrigerating coils so far as air movement is concerned, and provided with doors or slides through which the contained goods may be seen and which may be opened for convenient access.

An object of my invention is to provide means for the storage of food stuffs such as fresh fruits and vegetables, whereby troubles from dehydration and mold formation can be eliminated.

A further object is to provide storage means J in which high humidity and low temperature can be maintained when desired, to keep vegetables in crisp condition and even to restore crispness to vegetables which have become wilted or dried in shipment.

Another object is .to provide a storage and display cabinet with individual compartments so arranged that obtaining access to any one compartment does not involve loss of cold air from adjacent compartments.

A further object is to provide food storage means of the kind described with individual compartments having horizontally extending shelves forming baffles which limit the cross sectional area of the storage space, with consequently reduced convection circulation.

Still another object is the provision of storage means in which the contained goods are clearly visible and readily accessible to the customer or sales person.

With these and other objects in view, my invention consists in the construction, arrangement and combination of the various parts of my device whereby the objects contemplated are attained, as hereinafter more fully set torth, pointed out in my claims and illustrated in the accompanying drawings, in which:

Figure 1 is a front elevational view of a storage and display cabinet embodying my invention.

Figure 2 is a horizontal cross sectional view taken on the line 22 of Figure 1.

Figure 3 is a vertical sectional view on the line 33 of Figure 1.

Figure 4 is a fragmentary vertical sectional view taken on the line 44 of Figure 3.

Figure 5 is a perspective view showing a possible type of construction for .the assembly of the individual compartments.

Figure 6 is a perspective view of asliding closure panel.

In the drawings I have used the reference numeral ll] to indicate generally an outer cabinet having walls of insulating material as is customary with refrigerated display cabinets. A re frigerating coil I2 is provided in the topof the cabinet in the usual manner. Mounted within the cabinet are individual compartments C which for convenience may be assembled on a rack or framework Mso that they can be installed or removed in the cabinet H] as a single unit.

The compartments C' are preferably constructed of sheet metal or any material having good heat conductive qualities. They are mounted in such a manner that substantial space 15 provided between adjacent compartments, and above, below and behind the compartments so that the air in the cabinet cooled by the refrigeration coil 12 may circulate freelyand have access to all sides of the compartments except at the front. The front edges of the compartments are preferably connected by apan'el 16 through which each compartment opens individually. In the unit assembly su gested, the panel 15' may conveniently be attached to the supporting framework M so that it forms apart of the assembly. When, the assembly is inserted in the casing I'O it rests on horizontal supporting members l8 and the panel 16 makes a sealing engagement around all of its edges, as indicated, for example, at it and 22 in Figure2, and 24 and '26 in Figure 3. With the panel fitted in this way, there can be no substantial escape from the cabinet of the air which circulates over .the coil l2.

The unit assembly which I have described greatly facilitates cleanin or repair of the cabinet. ,If a drain clogs up or if refrigerating coils or connections need attention, access is relatively easy, without anynecessi'ty I01 dismantling operations which might mar or damage the cabinet.

The front of the. cabi'netis provided with slid ing, doors indicated generally by the. numeral .28. These doors may be mounted tor sliding operation in ways. well known in the refrigerator cabinetla-rt. To minimize neat leakage they -are-preferably provided with multiple. glass v35) as: shown in Figures 2 and 3. The advantages of my invention are more readily attained if one such door is provided for each compartment C so that cold air islost from only one compartmentwhen a-door is opened.

I have 'foundthat proper storage-condi-tionsior fruits, vegetables and meats as met in the usual grocery store must involve among other things the provision of a suitable low temperature, high humidity and minimum air circulation.

As regards the requirement of low temperature, it will be understood that any desired temperature may be reached by suitable adjustment of the refrigerating equipment supplying the coil l2. For proper storage of fruits and vegetables, I find a temperature in the range of 34 to 38 F. to be desirable; for meats, a slightly lower temperature is preferable. With conventional food storage cabinets the maintenance of such low temperatures has involved relatively high circulation velocities, and attendant rapid dehydration of the foods, the moisture absorbed from the foods by the rapid current of air being 1 lost by deposit on the refrigerating coils.

The dehydration problem, is so serious that as a matter of practical fact all refrigerated grocery cases for fresh goods, so far as I am aware, are operated at temperatures higher than what I have recommended. At the higher temperatures the velocityof air circulation is lower, and the humidity of the air is higher. Dehydration troubles are reduced, but along with the higher temperatures and higher humidity come mold and decay.

An important contribution to the effectiveness of my apparatus, however, results from the fact that five walls of each compartment are exposed 1 to the cold air circulating over the coil l2, so that there is a large amount of conducting surface with relation to the volume of the compart ment. With this large conducting area, the desired temperature can be maintained within the compartment with only a very moderate differenup with warm goods, the adjacent compartments act much like blocks of ice on each side, quickly cooling the new goods. Similarly, when a compartment is opened at the time a sale is made, some cold air will be lost but the temperature in the compartment will be quickly brought down to the desired pointagain by heat transfer to adjacent compartments as well as to the circumambient air.

With regard to maintaining theproper humid ity, the first feature of importance is that the interior of each compartment is isolated from the air circulating over the coil I! so that the air in the compartment is not dehydrated by the usual deposit of moisture on the colL The large surface area of the compartments makes possible adequate refrigeration without a wall temperature so low as to cause excessive condenser-'- tion. Hence, as a practical matter it is possible to maintain any ordinary "degree of humidity which is desired within the compartment. When higher than normal humidity is wanted, the vegetables may simply be sprinkled or sprayed with water. This may be necessary with goods which have just been put into the cabinet, after having dried out somewhat in previous shipment or storage. Even vegetables freshly picked from the garden during a dry spell may be improved by storage at low temperature and high humidity. They absorb moisture, become more crisp and appetizing, and cook faster.

With regard to air circulation, I have found it advantageous to restrict the cross section of storage space through which convection c rculation can take place to a value which may be stated roughly as a maximum of about 200 square inches. Where the apparatus illustrated in my drawings represents a commercial size display case, I have found it desirable to break up the space within the compartments. The individual compart-; ments themselves may conform tothis specification, or where the compartments are larger the space within them may be broken up by providing horizontal shelves 32 which serve as baiiles to reduce the uninterrupted cross sectionalarea below the approximate value indicated. In the cross sectional view of Figure 4,-for example, the portions A and B into which the compartment is divided by the shelf 32 are each of less than 200 inches cross sectional area. Furthermore, the provision of a shelf of this kind facilitates the neat display and convenientaccessibility of numerous different kinds of produce. The shelf may rest loosely. on support 33, so that it can be easily removed to facilitate cleaning of the compartment.

Limitation of the cross-sectional area has the further effect that no part of the interior of the compartment, when made as shown in thedrawings, can be more than a certain distance from a refrigerated wall. -For example, if the portions A and B in Figure 4 have the maximum areaof 200 square inches, no part of one of these por tions can be more than about 14, inches from a.

refrigerated wall. This makes for uniformity of temperature conditions throughout the com- [I I have found that even at 200 square inches when the compartments are only a third to a half full there will be enough freedom of circulation to cause slight dehydration. On the otherhand, with the compartments packed 'full there may be a little trouble with moldy cente'r"mold or decay taking place in the foodstuffs in the center of the compartment, farthest from the cold walls.

2. Moist air, preferably at the dew point, contaming more moisture than the stored products.

ucts.

Particularly for use in self-serve stores, my apparatus has the advantage that it keeps fruits and vegetables in first class condition, yet perfectly visible to the public in such a 'waythat ready and immediate access may be hadto the items which'the customer secs. 1

Carelessness on the part of a customer or salesperson in leaving a compartment open will have no serious effect on the adjacent compartments or onthe goods stored, therein.

Some changes maybe made in the construction and arrangement'of the parts oftmy device without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims any modified forms of struc- 3. Minimum circulation of air over the prodture, or use of mechanical equivalents, which may be reasonably included within their scope.

I claim as my invention:

1. Refrigerated storage means comprising a plurality of spaced-apart compartments having walls of conducting material, disposed within a refrigerated casing, and baflies Within said compartments so arranged that at any place within the compartment a vertical cross section on a plane transverse to the length of the compartment will have not more than 200 square inches of area throughout which unrestricted convection circulation may take place.

2. In a food storage and display cabinet, a refrigerated casing, and independent compartments therein, each of said compartments being arranged so that a vertical cross section transverse to the length of the compartment has not more than 200 square inches of area throughout which unrestricted convection circulation can occur.

3. In food storage and display means, a refrigerated cabinet, a plurality of compartments therein, said compartments having walls of conducting material, being exposed to refrigeration on top, bottom and sides, and opening individually to the outside of said cabinet, and means in each compartment whereby the maximum area throughout which unrestricted convection circulation may take place, on a vertical cross section transverse to the length of the compartment,. is limited to approximately 175 square inches.

4. A self-serve food merchandiser including an outer heat-insulated casing, refrigerating means therein, a plurality of metal-walled compartments in said casing, means whereby the opening of each compartment is isolated from air circulating over the refrigerating means, individual windowed closures for each compartment, and means in each compartment limiting the maximum area throughout which unrestricted convection circulation can take place, on a vertical cross section transverse to the length of the compartment, to approximately 175 square inches.

5. A self-serve food merchandiser including an outer heat insulated casing, refrigerating means therein, a plurality of compartments mounted on a rack for installation in and removal from said casing as a single unit, said compartments having walls of conducting material and being spaced apart on said rack so that each compartment is exposed to refrigeration on top, bottom and sides, means whereby the opening of each compartment is isolated from the air circulating over the refrigerating means, individual doors for each compartment, and windows in said doors through 1 which the goods in said compartments may be seen.

6. In food storage and display means, a refrigerated cabinet, and a-plurality of compartments therein having walls of conducting material, said compartments being exposed to refrigeration on one end, top, bottom and sides and being of such shape and size that no point in the interior of a compartment is more than fourteen inches from one of said refrigerated conducting walls, an individual door in each compartment opposite said one end, and a window in each door through which the goods in the compartment may be seen.

EDWARD M. STILES. 

